For the following questions answer them individually
The value of $$\left(\frac{1}{\sqrt{9} - \sqrt{8}} -\frac{1}{\sqrt{8} - \sqrt{7}}+\frac{1}{\sqrt{7} - \sqrt{6}}-\frac{1}{\sqrt{6} - \sqrt{5}}+\frac{1}{\sqrt{5} - \sqrt{4}} \right)$$ is
A candidate scoring 25% marks in an examination fails by 30 marks while another candidate who scores 50% marks gets 20 marks more than those required to pass. The pass percentage is
Harish divides two sums of money among his four sons Naresh, Vipin, Bhupesh, and Yogesh. The first sum is divided in the ratio 4 : 3 : 2 : 1 and second in the ratio 5 : 6 : 7 : 8. If the second sum is twice the first, then the largest total is received by
If points (t, 2t), (-2, 6) and (3,1) are collinear, then t is equal to
A contractor undertakes to do a piece of work in 40 days. He engages 100 men at the beginning and 100 more after 35 days and completes the work in stipulated time. If he had not engaged the additional men, how many days behind schedule would it be finished?
4 men and 6 women finish a job in 8 days, while 3 men and 7 women finish it in 10 days. In how many days will 10 women finish it?
A dishonest dealer professes to sell his goods at cost price. But he uses a false weight and thus gains $$6\frac{18}{47}\%$$ . For a kg, he uses a weight of
A man rows 20 km upstream and back again to the starting point in 110 minutes. If the speed of the stream is 2 kmph, then the speed of rowing in still water is
A number consists of two digits whose sum is 8. If 18 is added to the number, its digits are interchanged. The number is